McMaster said Iran has a network of proxies in Syria, Yemen and Iraq, which could turn against the governments, according to the news agency.

“What’s particularly concerning is that this network of proxies is becoming more and more capable, as Iran seeds more and more …destructive weapons into these networks,” McMaster said at the conference.

In the same day, Iranian President Hassan Rouhani said his country would stand by its commitment to the 2015 international nuclear agreement, Reuters reports.

“After signing a contract, haggling with it is ridiculous,” Rouhani said at an event in New Delhi.

U.S. President Donald Trump wants to make changes to the agreement that made it possible to lift sanctions against Iran.

“If the U.S. violates this agreement… you will see that America will regret this decision,” Rouhani said.